svn commit: r364946 - head/sys/kern

[Warner Losh]

Author: imp
Date: Sat Aug 29 04:30:12 2020
New Revision: 364946
URL: https://svnweb.freebsd.org/changeset/base/364946

Log:
  Move to using sbuf for some sysctl in newbus
  
  Convert two different sysctl to using sbuf. First, for all the default
  sysctls we implement for each device driver that's attached. This is a
  pure sbuf conversion.
  
  Second, convert sysctl_devices to fill its buffer with sbuf rather
  than a hand-rolled crappy thing I wrote years ago.
  
  Reviewed by: cem, markj
  Differential Revision: https://reviews.freebsd.org/D26206

Modified:
  head/sys/kern/subr_bus.c

Modified: head/sys/kern/subr_bus.c
==============================================================================
--- head/sys/kern/subr_bus.c	Sat Aug 29 04:30:06 2020	(r364945)
+++ head/sys/kern/subr_bus.c	Sat Aug 29 04:30:12 2020	(r364946)
@@ -260,36 +260,33 @@ enum {
 static int
 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
 {
+	struct sbuf sb;
 	device_t dev = (device_t)arg1;
-	const char *value;
-	char *buf;
 	int error;
 
-	buf = NULL;
+	sbuf_new_for_sysctl(&sb, NULL, 1024, req);
 	switch (arg2) {
 	case DEVICE_SYSCTL_DESC:
-		value = dev->desc ? dev->desc : "";
+		sbuf_cpy(&sb, dev->desc ? dev->desc : "");
 		break;
 	case DEVICE_SYSCTL_DRIVER:
-		value = dev->driver ? dev->driver->name : "";
+		sbuf_cpy(&sb, dev->driver ? dev->driver->name : "");
 		break;
 	case DEVICE_SYSCTL_LOCATION:
-		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
-		bus_child_location_str(dev, buf, 1024);
+		bus_child_location_sb(dev, &sb);
 		break;
 	case DEVICE_SYSCTL_PNPINFO:
-		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
-		bus_child_pnpinfo_str(dev, buf, 1024);
+		bus_child_pnpinfo_sb(dev, &sb);
 		break;
 	case DEVICE_SYSCTL_PARENT:
-		value = dev->parent ? dev->parent->nameunit : "";
+		sbuf_cpy(&sb, dev->parent ? dev->parent->nameunit : "");
 		break;
 	default:
+		sbuf_delete(&sb);
 		return (EINVAL);
 	}
-	error = SYSCTL_OUT_STR(req, value);
-	if (buf != NULL)
-		free(buf, M_BUS);
+	error = sbuf_finish(&sb);
+	sbuf_delete(&sb);
 	return (error);
 }
 
@@ -5464,13 +5461,13 @@ SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | 
 static int
 sysctl_devices(SYSCTL_HANDLER_ARGS)
 {
+	struct sbuf		sb;
 	int			*name = (int *)arg1;
 	u_int			namelen = arg2;
 	int			index;
 	device_t		dev;
 	struct u_device		*udev;
 	int			error;
-	char			*walker, *ep;
 
 	if (namelen != 2)
 		return (EINVAL);
@@ -5501,34 +5498,21 @@ sysctl_devices(SYSCTL_HANDLER_ARGS)
 	udev->dv_devflags = dev->devflags;
 	udev->dv_flags = dev->flags;
 	udev->dv_state = dev->state;
-	walker = udev->dv_fields;
-	ep = walker + sizeof(udev->dv_fields);
-#define CP(src)						\
-	if ((src) == NULL)				\
-		*walker++ = '\0';			\
-	else {						\
-		strlcpy(walker, (src), ep - walker);	\
-		walker += strlen(walker) + 1;		\
-	}						\
-	if (walker >= ep)				\
-		break;
-
-	do {
-		CP(dev->nameunit);
-		CP(dev->desc);
-		CP(dev->driver != NULL ? dev->driver->name : NULL);
-		bus_child_pnpinfo_str(dev, walker, ep - walker);
-		walker += strlen(walker) + 1;
-		if (walker >= ep)
-			break;
-		bus_child_location_str(dev, walker, ep - walker);
-		walker += strlen(walker) + 1;
-		if (walker >= ep)
-			break;
-		*walker++ = '\0';
-	} while (0);
-#undef CP
-	error = SYSCTL_OUT(req, udev, sizeof(*udev));
+	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
+	sbuf_cat(&sb, dev->nameunit);
+	sbuf_putc(&sb, '\0');
+	sbuf_cat(&sb, dev->desc);
+	sbuf_putc(&sb, '\0');
+	sbuf_cat(&sb, dev->driver != NULL ? dev->driver->name : '\0');
+	sbuf_putc(&sb, '\0');
+	bus_child_pnpinfo_sb(dev, &sb);
+	sbuf_putc(&sb, '\0');
+	bus_child_location_sb(dev, &sb);
+	sbuf_putc(&sb, '\0');
+	error = sbuf_finish(&sb);
+	if (error == 0)
+		error = SYSCTL_OUT(req, udev, sizeof(*udev));
+	sbuf_delete(&sb);
 	free(udev, M_BUS);
 	return (error);
 }